Osteosarcoma: an immunophenotypic study for characterization and behavior.

Abstract
Background: Osteosarcoma is the most common primary bone tumor occurring in second and third decades of life with a second peak later. Biopsy (needle or incision) is necessary for diagnosis along with imaging modalities (X-ray, CT scan etc) and serology. Due to diagnostic dilemma in certain cases and for prognosis of patients, immunohistochemistry is increasingly used. Aims: To assess the pathologic features and determinants of osteosarcoma in patients of the Indian subcontinent that would put an insight into its appearance and behavior. Methods and Material: Forty cases of biopsy proven osteosarcoma were selected over a period of three years. Histopathology was done for tumor typing, along with serology (pre and post-operative serum alkaline phosphatase). In all cases TNM staging and immunohistochemistry for antibodies to Osteonectin (ON) (diagnosis), S100 (differentiation), Ki 67 and Her2 (prognosis) was done. Results: Serum alkaline phosphatase was high in 37 (92%) cases initially and remained high in metastatic and recurrent lesions. Osteonectin was positive in 38 (95%) cases, S100 in 31 (77%), Ki 67 showed overlapping labeling indices between 4.8-18.8% and Her2 showed more positivity in higher stage tumors. Conclusions: Biopsy (along with imaging) is mandatory to diagnose osteosarcoma. Osteonectin is a good immunohistochemical marker to differentiate osteosarcoma from its mimics. For prognostication, serum alkaline phosphatase, post chemotherapy tumor necrosis (more than 90%), lack of Her2 expression are good parameters. S100 and Ki67 were found to have limited role in diagnosis and prognosis of osteosarcoma.
Description
Keywords
alkaline phosphatase, immunohistochemistry, osteonectin, osteosarcoma
Citation
Mandal PK, Chatterjee S, Ray S, Roy S, Chandra S, Basu N, Biswas S K. Osteosarcoma: an immunophenotypic study for characterization and behavior. Bangladesh Journal of Medical Science. 2014; 13(4): 443-448.